Architectural_Design_with_SketchUp

Architectural Design with SketchUp
It should be noted here that for computational efficiency, the number of “bounces” (or
material interactions) is typically limited to a number that is low enough to reduce computation
time, yet high enough to make the rendering look realistic. You can often experiment
with this setting in your rendering software.
The following natural phenomena can be simulated by rendering software. Actual implementation
and quality of the effects can vary among rendering software, though.
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Material appearance—This is commonly called shading and includes the interaction
between light and a surface’s material.
Texture—This is the photographic appearance of the material. Often, seamlessly repeating
images are used to represent a particular material (e.g., a brick pattern), but this could be
accomplished by single images or a computational method as well (e.g., for solid colors or a patterned
surface). SketchUp’s materials are all seamlessly repeating tiled images. (See Figure 5.7.)
Figure 5.7: Various surface textures (rusty metal, wood, paper, canvas, solid colors)
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Surface roughness simulation—Bump mapping or displacement mapping can at least add
the appearance of geometric detail and surface irregularities to an otherwise flat surface.
Displacement mapping typically goes further than bump mapping in that the underlying
geometry is modified. Bump mapping modifies only light reflection behavior. (See Figure 5.8.)
Figure 5.8: Material bumpiness: patterned rubber, natural stone, canvas
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